Good to hear from you! No headway on the MAF housing - We have tested a few in house and have determined that the filter was too tight on the housing causing it to collapse on the few we did receive.
As far as the 57i kit I'll assume you are talking about this... http://www.knfilters.com/search/prod...?Prod=57S-4000
unfortunately the filter is not sold separately and is only sold out of our Warrington England plant, if you were to order one it would take months for it to get here because we do not stock the 57i kits at our US facility.
If you have any questions please let me know! Have a great day.
Warranty / R&D Department
Ph: 800-858-3333 X-4161